presiding, the jury rendered a verdict of acquittal on the ground of unsound mind; but no medical expert had testified that Cole was insane. In the course of my examination as an expert witness, the court asked me whether I thought "that Cole, at the time he committed the act for which he was under trial, knew the difference between right and wrong, and that the act was in violation of the law." To which I replied in effect that "Cole, being suddenly confronted by the man who had wronged him, did not probably consider whether the act which he was about to commit was in violation of the law or not." If the jury made use of this reply to pronounce him insane, the responsibility of their verdict does not rest upon me. Their verdict of "unsound mind" was given, as it has been in many similar cases, because they did not think he ought to be punished for the act, and they were quite willing to give a very broad and partial interpretation to any testimony which in the remotest degree seemed to favor the defense. Subsequently, from several sources, I learned that my testimony, inferred only from the verdict, had been subjected to criticism.
The question put to me by the judge, although not so broad as it is usually made, no doubt had in view the legal definition or tests of unsound mind, and which, with a few slight modifications, has been incorporated into most systems of jurisprudence. But no legal definition of unsound mind can ever be properly made; and for the simple reason that no scientific definition is possible. The latter fact has generally been admitted by writers upon mental disease; but, nevertheless, they have often attempted to make what they are. pleased to term approximate definitions, for the purpose, as they have declared, of furnishing at least a guide in the proper direction. Upon these approximate definitions the law-makers have constructed their legal definitions or tests; no longer intended as guides simply, but as authoritative and sharply defined distinctions, which the courts are compelled to recognize. Whether these tests be applied in a scientific or legal sense, they are in my opinion unsound, unjust, and confusing; they are calculated to mislead the judgment rather than to direct it to a proper conclusion. They ought, therefore, to be abandoned, and the whole matter left to the common sense of the jurors, aided and enlightened by the testimony, the arguments of the counsel, and the exposition of the courts.
4. While, in what I have said, I trust I have shown a purpose to defend my professional brethren, when appearing in the rôle of experts in lunacy, against unjust criticism, by maintaining the undeniable proposition that, other things being equal, they are the most trustworthy witnesses, I am at the same time prepared to say that they are not the only persons or classes of persons whose opinions as experts may be valuable in matters of this sort, or whose opinions might not, in some cases, be safely substituted for their own.
In reference to questions of sanity or insanity, most men of intelli-
